text: 2,4-Dinitrophenylhydrazine (2,4-DNPH or DNPH) is the organic compound CH(NO)NHNH. DNPH is a red to orange solid. It is a substituted hydrazine. The solid is relatively sensitive to shock and friction. For this reason DNPH is usually handled as a wet powder. DNPH is a precursor to the drug Sivifene.